CN102055453A

CN102055453A - Direct-current solid electronic switch

Info

Publication number: CN102055453A
Application number: CN 201010623344
Authority: CN
Inventors: 荆涛; 孙向亮; 周勇军; 水冰
Original assignee: No206 Institute Of China North Industries Group Corp
Current assignee: No206 Institute Of China North Industries Group Corp
Priority date: 2010-12-31
Filing date: 2010-12-31
Publication date: 2011-05-11
Anticipated expiration: 2030-12-31
Also published as: CN102055453B

Abstract

The invention relates to a direct-current solid switch, which realizes high speed switch property and higher performance to price ratio on the basis of a P-channel insulated gate field effect pipe, a gate drive circuit, a gate circuit, an input protection circuit and an electrical coupling unit. The P-channel insulated gate field effect pipe is used as a switch control component to input control signals which are non-isolated or isolated switching value signals; the non-isolated or isolated switching value signals respectively enter the gate circuit to be judged in the quality and reshaped through the input protection circuit and the electrical coupling unit; generated switching value control signals are transformed through the gate drive circuit; gate control signals controlling the P-channel insulated gate field effect pipe to communicate are obtained, thus the direct-current solid switch with high switching-on and off speed and high reliability is obtained. The invention has the advantages of simple hardware circuits, high reliability, high-speed switching-on and off property, high current control capability, higher performance to price ratio and is widely used in the field of network, communication, IT household electrical appliances, industrial automation and the like.

Description

A kind of direct-current solid-state electronic switch

Technical field

The invention belongs to technical field of industrial automatic control, relate in particular to a kind of solid electronic DC switch, be mainly used in the industrial control field break-make of DC circuit is controlled.

Background technology

In industrial control system, often need control connecting and disconnecting of the circuit, it generally carries out break-make by the I/O switching value to relay and controls and realize.At present, the relay that domestic industrial control field is commonly used comprises two kinds of mechanical type and solid electronic formulas, because different separately operation principles has been also for its application has brought different restrictions, subject matter is:

(1) adopt the subject matter of mechanical relay to be that its switching frequency is lower, and Transistor-Transistor Logic level can't directly be controlled its break-make, drive circuit that need be extra; In addition, adopt mechanical relay also can bring the problem of noise and EMI radiation.

(2) adopt solid electronic formula relay to have higher switching frequency, but big current switching control ability is limited, it is comparatively complicated that realization has the electronic switch of electrical isolation function, the price height, and antijamming capability is relatively poor.

Summary of the invention

The technical problem to be solved in the present invention is to overcome the deficiencies in the prior art, provides a kind of and has not only satisfied big current switching demand for control, but also has the speed-sensitive switch characteristic and than the new DC solid electronic switch of high performance-price ratio.

For achieving the above object; the technical solution used in the present invention is: adopt P raceway groove insulated gate field-effect pipe (P-MOSFET) as the switch motion executive component, realize the direct-current solid-state electronic switch in conjunction with gate driver circuit, electrical couplings unit, input protection circuit and gate circuit.Described direct-current solid-state electronic switch adopts the intermediate link of gate driver circuit as gate circuit and P-MOSFET; to be converted to the grid control signal of control P-MOSFET break-make via the switching value control signal that gate circuit generates; and electrical couplings unit and input protection circuit are as the intermediate link of gate circuit and multichannel input switch amount signal; with the non-isolation or the isolating switch amount conversion of signals of input is unified gate circuit input signal; this signal forms the switching value input control signal of gate driver circuit after the gate circuit shaping, realize the function of electronic DC switch.

Described gate driver circuit comprises resistance and NPN type triode Q1.Wherein, the base stage of triode links to each other with control signal VCO input by resistance R 1, emitter links to each other with ground level GND by resistance R 4, and an end of collector electrode links with input terminal voltage VIN by resistance R 3, and the other end is by resistance R 2 output grid-control voltage VOUT; Its operation principle is: when VCO was high level, the triode saturation conduction by the dividing potential drop of resistance R 3 with R4, obtained the VOUT voltage less than VIN, and when (VOUT-VIN) satisfied the gate turn-on threshold voltage of P-MOSFET, P-MOSFET is conducting also; When VCO was low level, triode ended, this moment VOUT=VIN, thereby the grid voltage of P-MOSFET is 0 volt, turn-on condition is satisfied, P-MOSFET ends, thereby finishes the conversion of switching value signal to the gate turn-on control signal of P-MOSFET.

Described gate circuit is connected in series by NOR gate and Schmidt trigger.By to arbitrating and shaping, form the switching value control signal from the control switch amount of input protection circuit and electrical couplings unit.

Described electrical couplings unit comprises resistance and optocoupler.Wherein, resistance R 5 is connected in the switching value input circuit, be used to limit input current to satisfy the optocoupler turn-on condition, resistance R 6 is connected on the optocoupler output, the drop-down ground connection of one end, the other end links to each other as the input stage of the control switch amount signal AND circuit after changing, thereby realizes the isolation of input switch amount signal and output control switch amount signal.

Described input protection circuit comprises resistance, voltage stabilizing didoe, clamp diode and electric capacity.Wherein, after input switch amount signal obtains switching value signal that amplitude dwindles through divider resistance R7, R8; again through behind the voltage stabilizing didoe V3 and clamp diode V4 in parallel with it; with output switching value voltage of signals amplitude limitation in the reasonable input range of gate circuit; but be connected in parallel on then filtering switching value of the electric capacity signal between output and the ground peak voltage; reduce of the influence of input switch amount noise, thereby realize the protection and the amplitude limit function of non-isolated switching value input signal gate circuit.

According to direct-current solid-state electronic switch of the present invention, both can realize that the switching value input control that also can realize non-isolation type was controlled in the switching value input of isolated form, dual mode all only needs single power supply can realize controlled function.

The present invention has following characteristics compared with prior art:

1. select for use P-MOSFET as make-and-break control switch, it is little to have a volume, and switching speed is fast, current density is big and the characteristic of low on-resistance, and can select model many, can satisfy the needs of different switches controls.

2. select for use triode and resistance to constitute the gate driver circuit of P-MOSFET, it is simple to have the circuit structure form, high reliability features.

3. only need single power supply can realize isolating or the switching value control signal input of non-isolation type, the circuit structure form is simple, and cost is low.

4. by the combination of input protection circuit and gate circuit, expand input switch amount voltage of signals scope on the one hand, overvoltage and reverse connecting protection are provided, reduced the electronic switch misoperation possibility that causes by input noise on the other hand.

5. select the prime of gate circuit as gate driver circuit for use, even the back input switch amount signal of having guaranteed to power on does not exist at every turn, the output of this electronic switch also has fixing on off operating mode, has avoided false triggering.

Hardware circuit of the present invention is simple, and the reliability height has speed-sensitive switch characteristic and big Current Control ability and high cost performance, can be widely used in fields such as network, communication, info class household electrical appliances, industrial automation.

Description of drawings

Fig. 1 is the block diagram of system of the present invention

Fig. 2 is a gate driver circuit fundamental diagram of the present invention

Fig. 3 is an electrical couplings cell operation schematic diagram of the present invention

Fig. 4 is an input protection circuit fundamental diagram of the present invention

Embodiment

The present invention adopts P-MOSFET as make-and-break control switch, by design gate driver circuit and necessary peripheral circuit realize big electric current, at a high speed, the DC electronic solid-state switch of high reliability.

Referring to Fig. 1, in the present embodiment, electronic DC switch is made up of one tunnel electrical couplings unit, one road input protection circuit, NOR gate D1, Schmidt trigger D2, gate driver circuit, P raceway groove insulated gate field-effect pipe (P-MOSFET) V1 and fast recovery diode V2, the hardware method of attachment is: the input of electrical couplings unit is CON1+ and CON1-, link to each other with the switching value signal input of isolating, output links to each other with the input of D1; The input of input protection circuit is CON2, links to each other with the switching value signal input of non-isolation, and output links to each other with the input of D1; Pass through the D2 shaping again after two switching value signals are arbitrated through D1, obtain the control input control signal of gate driver circuit, carry out conversion, obtain the grid control signal of P-MOSFET V1 through gate driver circuit, thus the turn-on and turn-off of control V1; V2 is attempted by between the source electrode and drain electrode of P-MOSFET V1, is used to absorb because the due to voltage spikes that P-MOSFET V1 switch causes.The power supply power supply of this electronic switch has only one road VCC, both can realize that the switching value input control that also can realize non-isolation type was controlled in the switching value input of isolated form, has simplified circuit structure.The both positive and negative polarity of output switching terminal is respectively VIN and VOUT; The load characteristic of electronic switch depends on the characteristic of P-MOSFET V1 fully.

Gate driver circuit as shown in Figure 2, embodiments of the invention adopt triode Q1 and resistance R 1, R2, R3, R4 to form gate driver circuit, and wherein Q1 is a NPN type triode, and its operating state is saturation conduction or ends.Acting as of R1 limits the Q1 base current, and the one end links to each other with input control signal VCO end; The end of R3 links to each other with electronic switch output plus terminal VIN, and the other end links to each other with R2 with the collector electrode of Q1, and R2 is an output current limiting resistance, and its other end is grid output control voltage VOUT; R3 and R4 constitute divider resistance, when the Q1 conducting, and VOUT=VIN * R4/ (R3+R4), when Q1 ends, VOUT=VIN, thus of the conversion of incoming level control signal finished to gate driving control signal, and the gate-on voltage thresholding of P-MOSFETV1 is relevant among the value of R3 and R4 and Fig. 1.

Electrical couplings unit as shown in Figure 3, example of the present invention adopts resistance R 5, R6 and optocoupler Q2 to form the electrical couplings unit, wherein R5 is connected in the switching value input signal loop as current-limiting resistance, CON+ and CON-be the positive and negative terminal of corresponding switching value input signal respectively, the output collector electrode of optocoupler Q2 directly links to each other with logic power VCC, emitter links to each other with signal after coupling amount output VO with resistance R 6, the other end of resistance R 6 links to each other with ground level, R6 plays drop-down effect, the low level that guarantees the switching value signal of output is 0 volt, and high level is (VCC-0.6) volt.

Input protection circuit as shown in Figure 4; embodiments of the invention adopt resistance R 7, R8,5.1V voltage stabilizing didoe V3, Schottky diode V4 and capacitor C 1 to form input protection circuit; wherein R7, R8 form the input bleeder circuit; the level of switching value input signal is limited between 0～VI * R2/ (R1+R2) volt; the V3 and the V4 that are connected in parallel on the R8 two ends then further are limited in this voltage in-0.3～5 volt; for the input of level gate circuit afterwards provides protection; capacitor C 1 is chosen 0.1 microfarad, is used for the absorbing high-frequency noise signal.

Claims

1. direct-current solid-state electronic switch, it is characterized in that: electronic switch is made up of electrical couplings unit, input protection circuit, gate circuit, gate driver circuit, P raceway groove insulated gate field-effect pipe V1 and fast recovery diode V2, and wherein P raceway groove insulated gate field-effect pipe V1 is a switch executing element; Electrical couplings unit and input protection circuit are as the intermediate link of multichannel input switch amount signal and gate circuit; with the non-isolation or the isolating switch amount conversion of signals of input is unified gate circuit input signal; described gate driver circuit is as the intermediate link of gate circuit and P raceway groove insulated gate field-effect pipe V1; the switching value control signal that gate circuit is generated is converted to the grid control signal of controlling P raceway groove insulated gate field-effect pipe V1 break-make; described fast recovery diode V2 is connected in parallel between the source electrode and drain electrode of P raceway groove insulated gate field-effect pipe V1, is used to absorb the due to voltage spikes that the switch of V1 causes.

2. a kind of direct-current solid-state electronic switch according to claim 1; it is characterized in that: described gate circuit is connected in series by NOR gate D1 and Schmidt trigger D2; to arbitrating and shaping, form the switching value control signal from the control switch amount of input protection circuit and electrical couplings unit.

3. a kind of direct-current solid-state electronic switch according to claim 1, it is characterized in that: described gate driver circuit is made of triode Q1 and resistance R 1, R2, R3, R4, wherein Q1 is a NPN type triode, the base stage of triode Q1 links to each other with control signal VCO input by resistance R 1, emitter links to each other with ground level GND by resistance R 4, one end of collector electrode links with input terminal voltage VIN by resistance R 3, and the other end is by resistance R 2 output grid-control voltage VOUT; When control signal VCO was high level, triode Q1 saturation conduction by the dividing potential drop of resistance R 3 with R4, obtained the VOUT voltage less than VIN, when VOUT-VIN satisfies the gate turn-on threshold voltage of P raceway groove insulated gate field-effect pipe V1, and the V1 conducting; When VCO was low level, triode Q1 ended, this moment VOUT=VIN, V1 ends; Thereby finish of the conversion of switching value signal to P raceway groove insulated gate field-effect pipe V1 gate turn-on control signal.

4. a kind of direct-current solid-state electronic switch according to claim 1, it is characterized in that: described electrical couplings unit is made up of optocoupler Q2 and resistance R 5, R6, wherein, resistance R 5 is connected in the switching value input circuit, be used to limit input current to satisfy the optocoupler turn-on condition, resistance R 6 one terminates at optocoupler Q2 output, and with the conversion after control switch amount signal and the input stage of gate circuit link to each other, the drop-down ground connection of the other end is realized the isolation of input switch amount signal and output control switch amount signal.

5. a kind of direct-current solid-state electronic switch according to claim 1; it is characterized in that: described input protection circuit is by resistance R 7; R8; voltage stabilizing didoe V3; clamp diode V4 and capacitor C 1 are formed; input switch amount signal is through divider resistance R7; R8 obtains the switching value signal that amplitude is dwindled; pass through voltage stabilizing didoe V3 in parallel and clamp diode V4 again with R8; with output switching value voltage of signals amplitude limitation in the input range of gate circuit; be connected in parallel on the capacitor C 1 filtering switching value signal peaks voltage between output and the ground; reduce of the influence of input switch amount noise, thereby realize the protection and the amplitude limit function of non-isolated switching value input signal gate circuit.

6. a kind of direct-current solid-state electronic switch according to claim 1 is characterized in that: described direct-current solid-state electronic switch is provided with the power supply of one road power supply, realizes isolated or non-isolated switching value input signal control.